Welding Process Guide
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Pre-flow and Post-flow Timing: Arc Start and Crater Protection

Pre-flow establishes gas coverage before arc initiation while post-flow protects the cooling molten metal and tungsten electrode from oxidation. Optimal timing is 1-2 seconds pre-flow for MIG/MAG, 2-3 seconds for TIG, and 5-10 seconds post-flow depending on material and thickness.

Flow Timing Optimization

  1. Pre-flow Setting. MIG/MAG: 1-2 seconds, TIG: 2-3 seconds. Ensures stable gas envelope before arc starts.
  2. Post-flow Setting. MIG/MAG: 3-5 seconds, TIG: 5-15 seconds depending on current and material sensitivity.
  3. Material Adjustments. Stainless steel and aluminum require longer post-flow due to oxidation sensitivity.
Flow Optimized

VARIGON® He30 for TIG

Why proper flow timing critical with VARIGON®: Premium gas investment requires optimal timing to prevent waste while ensuring complete protection during vulnerable arc start/stop phases.